CN1875148A

CN1875148A - Belt with variable grooves

Info

Publication number: CN1875148A
Application number: CNA2004800324804A
Authority: CN
Inventors: 汤玛斯·克劳休夫; 凯斯·费特兹派翠克
Original assignee: Albany International Corp
Current assignee: Albany International Corp
Priority date: 2003-11-03
Filing date: 2004-11-01
Publication date: 2006-12-06
Anticipated expiration: 2024-11-01
Also published as: CA2544515A1; ZA200604530B; BRPI0416124A; BRPI0416124B1; US7384516B2; NO20062522L; US20050115100A1; WO2005042835A1; EP1682718A1; RU2006115382A; AU2004286319A1; TWI338070B; JP4949848B2; RU2384663C2; TW200528611A; JP2007510826A; CN1875148B; KR101051669B1; KR20060123129A

Abstract

A belt (16) for use in a papermaking process, such as in a long nip press having a cylindrical press roller (12) and an arcuate pressure shoe (14) which define a nip (10). The belt has a nip load zone (36) which passes through the nip during an operation. The belt comprises a substrate (28) having a coating (34) on at least one surface thereof The substrate is in the form of an endless loop and has a longitudinal or machine direction. The coating has a plurality of grooves (42, 44) running in the machine direction, wherein grooves (44) in a center portion (64) of the nip load zone have at least one of a depth, width, cross-sectional shape, or spacing which is different from that of grooves (42) in outer portions (62) of the nip load zone so as to vary the void volume of the nipe load zone in a cross-machine direction in a desired manner.

Description

Belt with variable grooves

Technical field

The present invention relates on paper machine, fiber web is processed into paper products.Specifically, the present invention relates to the method and the device of the press operation relevant with producing paper.

Background technology

In the paper-making process, online at the paper machine forming section by fiber pulp being deposited to plastic metal wire, to form the fiber web that cellulose fibre is formed thereon.Discharge a large amount of water in the slurry at forming section, afterwards, just the fiber web that forms is directed into press section.Press section comprises a series of press. nips, and in nip, cellulosic fibrous web is compressed the effect of power, and this compression stress is extruded water from net.Paper web finally is directed into drying section, and drying section comprises the dryer drums of heating, and paper web is around rotary drum.The dryer drums of heating is reduced to desired level by evaporation with the moisture of paper web, to make paper products.

Because energy cost improves, and need remove moisture as much as possible all the more before paper web enters drying section.Reason is that dryer drums is generally heated internally by steam, and the cost relevant with producing steam may be very high, particularly when must be especially true when paper web is removed large quantity of moisture.

Usually, press section comprises a series of by the contiguous nip of cylindrical press roll to forming.In recent years, it is found that the long press. nips of use boot last is better than using the nip that is formed by paired adjacent press rolls.This is that paper web will pass long press. nips with the more time because compare with the nip that passes pressure roller formation.Paper web bears time of pressure in nip long more, just many more from the moisture of wherein removing, and therefore, it is just few more to remain in the moisture that need remove by evaporation in drying section in the paper web.

The present invention relates to the boot last long nip presses.In the long nip presses of this type, form nip between cylindrical press roll and the arcuate pressure shoe.Shoe has columned recessed surface, and its radius of curvature approaches the radius of curvature of cylindrical press roll.When roller and pressure shoe are closely pressed close to each other basically each other, form nip, long 5 to 10 times of the length of the nip that forms between comparable two pressure roller of its length along machine direction.Because this long nip press is 5 to 10 double-lengths of traditional double roll-in crusher nip, keep per square inch with two roll-in crushers under the extruding force same degree, cellulosic fibrous web so-called time of staying of pressurized in long nip press is long relatively.Therefore on paper machine, compare with conventional nip, the effect that this long nip press technology obtains is, increases substantially at the dehydrating amount of long nip press cellulose fibres net.

The boot-shaped long nip presses needs special band, as United States Patent (USP) 5,238, and the belt shown in 537.This belt design becomes these press fabrics of protection (be used for supporting, transport and de-fibering cellulose fiber net in moisture) not to be subjected to accelerated wear test, and these wearing and tearing are by the direct sliding-contact generation of carrying out on fixing shoe.This belt must have smooth-going impermeable surface, and fixing pressure shoe is crossed or slipped on this surface on glossy synovial membrane.Belt to be moving past nip with the roughly the same speed of press fabric, thus to press fabric apply to belt surface amount of friction minimum.

United States Patent (USP) 5,238, the belt of 537 shown types is by the woven of endless loop form being flooded synthetic polymerized resin and making.Preferably, resin forms on the inner surface of belt at least has the coating of certain predetermined thickness, and nationality is used for the yarn of woven with protection can directly not touch the arcuate pressure shoe assembly of long nip presses.Particularly this coating must have smooth-going, impermeable surface, and nationality slips on lubricated pressure shoe being easy to, and avoids any lubricating oil to penetrate belt composition and pollute one or more press fabrics and fiber web.

United States Patent (USP) 5,238, the base fabric of belt shown in 537 can be weaved by monofilament yarn with the single or multiple lift weave, and is woven into abundant opening, to allow impregnated material fully flood weaven goods.This has eliminated the possibility that forms any space in the finished belt.This space can make lubricator used between belt and the pressure shoe pass belt, and pollutes one or more press fabric and fiber web.Base fabric can be plain weave and forms, and is stitched into ring-type subsequently, and perhaps ring-type is made into tubular form.

When impregnated material is cured as when solid-state, it is mainly by the mechanical interlocked base fabric that is incorporated into, and wherein makes impregnated material through solidifying surround the yarn of base fabric.In addition, can have part chemical bond or bonding between the thread material of impregnated material through solidifying and base fabric.

Such as, United States Patent (USP) 5,238, long nip press belt shown in 537 is decided according to the size requirements of its long nip presses of installing, along its endless loop form, vertically measure have roughly 13 to the 35 feet length of (about 4 to 11 meters), and cross this structure measurement, cross measure goes out the width of roughly 100 to 450 inches (about 250 to 1125 centimetres).It should be noted,, make that the manufacturing of this belt is complicated more because base fabric requirement before the dipping synthetic polymerized resin is ring-type.

Often needing both also provided the resinous coat with predetermined thickness to it on its outer surface at the belt inner surface.By the two sides that applies belt, though the neutral bending axis of woven base fabric and belt (neutral axis) and non-coincidence, also can be more approaching with it.In this case, scratching the internal stress that is produced when bending around belt passes roller on the paper machine etc. will be not easy to cause coating from arbitrary of belt delamination to take place.

In addition, when the belt outer surface has the resinous coat of predetermined thickness, groove, blind boring or other cave, chamber or space can be formed on this surface, and not expose any part of woven.These are characterized as the water that extrudes from paper web in the press. nips temporary transient storage effect are provided.In fact, concerning some long nip press configurations, the voidage part that need on the belt outer surface, provide by groove, blind boring etc.

Though in whole paper-making process, uniformity and the drainage of keeping paper web as much as possible are constant, are still and can't avoid error.The characteristic of paper web as profile moisture (moistureprofile), may change in time.The profile moisture of paper web can influence the intensity and the quality of final products.For instance, go up moisture at laterally (CD) and change the excessive paper property that changes of may causing, as curling, and deterioration in quality.Therefore, must in paper-making process, control the CD profile moisture.

Compare with the prior art belt, the present invention can provide a kind of Improvement type belt, and it has the voidage of variation, to proofread and correct (homogenising) CD paper profile moisture.Specifically, for example, bear in nip at belt in the zone of compression stress, belt of the present invention can provide the groove with different depth.Groove with different depth improves the CD profile moisture of belt, and then strengthens product quality.Selectively, bear in nip at belt in the zone of compression stress, the present invention can provide has groove variation or difformity, dimension and/or size, width and length.Moreover, being combined with above-mentioned any variation, the present invention can change the orientation and/or the quantity of groove in this zone.

Summary of the invention

Therefore, the present invention is a kind of belt that is used for papermaking processing.Specifically, this belt can be used for long nip presses, and wherein this squeezer has cylindrical roller and arcuate pressure shoe, and both form nip together betwixt.

Belt of the present invention has nip load zone and two fringe regions, and can operate so that this nip load zone is passed nip when operation.This belt comprises on one surface that at least at least one has resin-coated layer, and wherein this belt is the form of the endless loop with vertical or machine direction.Resinous coat has a plurality of grooves, comprise a plurality of first grooves and a plurality of second groove, in the middle body of this nip load zone, first and second groove with the direction of longitudinal direction almost parallel on extend, wherein at least in one of the degree of depth, transverse shape, size or width or its combination, these a plurality of first grooves have difference with these a plurality of second grooves.

Hereinafter will be with reference to the accompanying drawings, describe the present invention in detail.

Description of drawings

Describe the present invention in detail below in conjunction with accompanying drawing, following explanation is the usefulness of example only, and the present invention is not limited to this, and among the figure, identical number designation is represented identical assembly and parts, wherein:

Fig. 1 is the side sectional view of long nip presses;

Fig. 2 is the cutaway view according to the belt of the embodiment of the invention; And

Fig. 3 is the exploded view of the nip load zone of belt shown in Figure 2.

The specific embodiment

Below will be with the formal specification preferred embodiment of the present invention of long nip press pressure shoe expelling belt.

In long nip presses shown in the side sectional view shown in Figure 1, be used to make the fiber web dehydration that is processed to paper products on the paper machine.Press. nips 10 is formed by smooth cylindrical press roll 12 and arcuate pressure shoe 14.Arcuate pressure shoe 14 has roughly the same radius of curvature with cylindrical roller 12.Can the distance between cylindrical roller 12 and the arcuate pressure shoe 14 be adjusted by (may be operably coupled to arcuate pressure shoe 14) such as hydraulic mechanisms, with the load of control nip 10.Smooth cylindrical press roll 12 can be the controlled arch crown roller that is engaged to arcuate pressure shoe 14, with the profile that obtains to be complementary with nip pressure on the horizontal cross.Usually, CD paper profile moisture presents " smile " or " frowning " shape.Its mechanical checkout is sometimes inoperative maybe can't to meet the demands.

Long nip press belt 16 extends through nip 10 with the sealing endless belt, and cylindrical roller 12 and arcuate pressure shoe 14 are separated.Press fabric 18 passes nip 10 with the fiber web 20 that is processed to paper, shown in arrow among Fig. 1.Fiber web 20 is supported by press fabric 18, and directly contacts with smooth cylindrical press roll 12 in nip 10.Selectively, fiber web 20 can be clipped between the two press fabrics 18 (not shown second press fabric) and pass nip 10.Long nip press belt 16 also moves past press. nips 10, as shown by arrows, that is clockwise direction as shown in Figure 1, and protection press fabric 18, and avoiding its directly sliding-contact on arcuate pressure shoe 14, and usually in the enterprising line slip of glossy synovial membrane.Therefore, long nip press belt 16 impermeable oil are not so press fabric 18 can be contaminated with fiber web 20.

Fig. 2 is the cutaway view according to the belt of the embodiment of the invention.As shown in the figure, belt 16 can comprise nip load zone 36 and fringe region 38.Nip load zone 36 is the zone that can pass in the belt between pressure roller 12 and the arcuate pressure shoe 14, and can compress therein, and this zone is belt zone involved in the present invention.On belt, fringe region 38 forms from belt edge 37 to nip load zone 36 zone, and adopts structure well known by persons skilled in the art.Nip load zone 36 can have fringe region 38 in its both sides on the cross-machine-direction of belt.Nip load zone 36 and fringe region 38 also extend at the belt machine run or vertically.

Belt 16 can comprise at least one layer, base structure as shown in Figure 3 or substrate layer 28.Yet belt 16 also can comprise additional layer.Layer 28 can be with horizontal or cross-machine-direction yarn 30 (watching from Fig. 3 side) non-woven constructions with vertical or machine-direction yarn 32 assembly forms, and as required, above-mentioned yarn can combine at mutual intersection point place, to form fabric.

Selectively, layer 28 is a weaving form.Transverse yarns is to be woven in vertical yarn top, below and warp thread therebetween.It should be noted that layer 28 can plain weave, by seam it is bonded into annular form then.It should be noted that in addition layer 28 can be weaved with single layer of woven or any other weaving-pattern well known to those skilled in the art and form.

In addition, layer 28 can be knitting or braided fabric, or spiral-link, and disclosed as the United States Patent (USP) 4,567,077 of Gauthier, its content is incorporated this paper at this into way of reference.Layer 28 also can be the form of thin plate or film, is extruded by polymeric resin material to form, and then the hole is set.Optionally, at least one this layer 28 can have the nonwoven mesh material fabric, and disclosed as the United States Patent (USP) 4,427,734 of Johnson, its content is incorporated this paper at this into way of reference.

Moreover, can will weave according to people's such as Rexfelt United States Patent (USP) 5,360,656 disclosed contents, nonwoven, knitting, weave, extrude or nonwoven mesh material material bands spiral twines, make layer 28, the content of this patent is incorporated this paper at this into way of reference.Therefore, layer 28 can comprise the spiral wound strips, wherein, by continuous seam, makes each spiral turns be engaged to next spiral turns, makes layer 28 vertically become ring-type.Have in the long nip press of this layer or the United States Patent (USP) 5,792,323 and 5,837,080 that the pressure shoe expelling belt is disclosed in common transfer, its content is incorporated this paper at this into way of reference.

To deposit, be coated with, flood or otherwise,,, to place at least one surface of belt 16 as polymer resin 34 with resin.Can be with coating or otherwise, polymer resin 34 is placed on the outer surface 24 of belt 16, that is, belt 16 when being used for long nip presses, this surface contact press fabric 18.In addition, can be coated with or otherwise, polymer resin be placed on the inner surface 22 of belt 16, that is belt 16 is when being used for long nip presses, this surface slides on the arcuate pressure shoe 14.Selectively, the inner surface 22 that polymer resin both can have been coated belt 16 is also coated outer surface 24.Polymer resin can impregnate layer 28, and makes belt 16 have impermeability to oil, water etc.Polymer resin coating 34 can be made by polyurethane, adopts 100% solid composite, is defined as solvent-free materials, in the process that is cured after it being applied to layer 28, can avoid forming bubble in polymer resin.Also can use other coating material, as rubber or class rubber compound.Which kind of situation no matter, resin bed can be identical or different, and can have identical or different firmness level.

Also can be after polymer resin solidify, inner surface 22 and/or outer surface 24 are ground and polished, so that the polymer resin coating has level and smooth and surface uniformly.

Polymer resin can be provided with groove 26 after solidifying in the outer surface 24 of belt 16.Specifically, can be by cutting, boring or alternate manner, (that is belt bears the zone of compression stress in nip load zone 36, it typically is the part of belt integral width) in the groove of different depth is provided, and make groove orientation to extend in the vertical.In one embodiment of the invention, groove 26 extends parallel to each other, yet other orientation also within the scope of the present invention.But as another selection mode of cutting and boring etc., can before polymer resin solidifies, in outer surface 24, be pressed into groove 26, or be molded into outer surface 24 (for example the time) by molding processing and manufacturing belt 16 by the squash type device.Be appreciated that to those skilled in the art, can easily utilize other method to form groove 26.Use term " groove " though note that this paper, what reality took place is to produce space or voidage in belt, to hold the liquid of taking out of.Can pass through to change shape, size, spacing and the orientation of " groove ", or any its compound mode, this voidage that obtains in the belt changes.

Fig. 3 is the exploded view of nip load zone 36 shown in Fig. 2.Fig. 3 also illustrates first groove 42 on the outer surface 24 and the exploded view of second groove 44.In addition, all digital sizes are all the usefulness of example, should not be considered as getting rid of other possibility.

First groove 42 and second groove 44 have first degree of depth 46 and second degree of depth 48 respectively.In addition, first groove 42 and second groove 44 have first outside width 50 and second outside width 52 respectively, and the first inboard width 54 and the second inboard width 56.Moreover first groove 42 and second groove 44 in the vertical can be continuous or discontinuous.In addition, first groove 42 and second groove 44 can be separated by so-called first land area 58 and second land area 60 between adjacent grooves.First land area 58 and second land area 60 can be regarded as: extend on the machine direction of belt 16 outer surfaces 24, be the narrow column through the curing polymer resin.Respectively, first and second gash depth 46,48 can have the numerical value of about 1.10mm and 1.5mm, first inboard and outside width 54,50 can have the numerical value of about 0.85mm and 1.18mm, and second inboard and outside width 56,52 can have the numerical value of about 0.85mm and 1.35mm.First land area 58 and second land area 60 can have the width of about 2mm and 1.88mm respectively.Be appreciated that first and/or second groove 42,44 and first and/or second land area 58,60 also can use other shape, size, spacing and orientation, and all within the scope of the present invention.

As shown in Figure 3, nip load zone 36 can comprise middle body 64, mid portion 66, and Outboard Sections 62.The groove 26 of middle body 64, mid portion 66 and Outboard Sections 62 can be of different sizes, orientation, shape and/or the degree of depth or its combination.For instance, middle body 64 can comprise the groove with single-width and degree of depth; Optionally, can comprise a plurality of first grooves 42 and a plurality of second grooves 44.Groove in the middle body 64 can be arranged by any way.In other words, this groove can be arranged like this: first groove 42 connects second groove 44 and connects first groove 42 or the like again, and perhaps a plurality of first grooves connect a plurality of second grooves and connect a plurality of first grooves or the like again.Moreover middle body 64 can comprise the groove with two or more different sizes, orientation, shape and/or degree of depth, and arranges with any compound mode.In addition, mid portion 66 also can comprise the groove with different size, shape and/or degree of depth with one of Outboard Sections 62 or both, and configuration in any of the above methods.Moreover to opposite side, Outboard Sections 62 or mid portion 66 can have different groove shapes from a side of nip load zone 36.

For instance, mid portion 66 can comprise the gash depth of staged phase change.As shown in Figure 3,72 places have the ID of about 1.4mm to the groove of mid portion 66 in the position, and 71 places have the degree of depth of about 1.3mm in the position, and 70 places then have the degree of depth of about 1.2mm in the position, promptly change with the increment of 0.10mm every 460mm.Have the groove of dark about 1.5mm for middle body 64, and Outboard Sections has the embodiment of dark about 1.1mm, this arranges advantageous particularly.This mainly can cause in the middle body 64 voidage to increase, and along with part 62 toward the outer side, voidage reduces.In brief, the arrangement of groove and characteristic can optimizations, when being converted to the big degree of depth of middle body 64 in the less degree of depth from Outboard Sections, make existing C D profile moisture evenly or improve.Note, decide on profile moisture to be adjusted, even can comprise the zone of not having groove or having depth zero.

Though groove is described as the transverse shape that has as shown in Figure 3 and by cutting or be shaped and provide, the present invention is not limited thereto.For instance, groove can have other transverse shape, also can obtain by alternate manner.For example, can by at belt circumferentially with spiral or locate mode, towards roughly vertical, clockwise or cutting counterclockwise or form the cutter sweep (as boring the formula device) of groove, groove 26 is set.In the case, can be with any compound mode configuration trench.In a kind of configuration, a groove has clockwise spiral cross-section, and connects to have the groove in counterclockwise cross section, connects to have groove of clockwise spiral cross-section or the like again.In addition, each groove 26 can be not exclusively and parallel longitudinal, and can change to some extent.In addition, a plurality of grooves 26 are oriented to is extending on the direction of (for example up to miter angle) at angle with the parallel longitudinal linear.

Say it, principle of the present invention is, change the voidage of groove in these zones (two fringe region and middle section), thereby for example, the zone with less available voidage can receive less moisture.For instance, in typical " frowning " type CD paper profile moisture, paper edge is done than paper is central.By reducing the voidage in zone, belt two edges, the moisture of removing from these zones of paper reduces, so that it is more even to leave the paper profile moisture of press. nips.Similarly, for typical " smile " type CD paper profile moisture, this voidage will be provided with on the contrary.

For those of ordinary skills, can easily make amendment, and above-mentioned modification does not exceed the scope of claims of the present invention foregoing.

Claims

1. endless belt that is used for the shoe-press machine, this squeezer has cylindrical roller and arcuate pressure shoe, both form nip jointly betwixt, described belt comprises nip load zone, this nip load zone has a width on cross-machine-direction, operate described belt, so that in operation, the described belt that has described nip load zone passes described nip, and described belt comprises:

Base material;

At least one coating at least one side of described base material;

Desired pattern in described layer comprises groove; And

Described desired pattern is made for, on the width of described nip load zone, described nip load zone has such voidage, described voidage is resultant by the groove with different in width, transverse shape, spacing or one or more above-mentioned feature combinations, perhaps, be combined with different depth, so that change described voidage in the expectation mode.

2. belt according to claim 1, wherein said nip load zone comprise two Outboard Sections, and each Outboard Sections is positioned at a side of middle body.

3. belt according to claim 2, wherein said nip load zone comprise two mid portions, and each mid portion is positioned at a side of described middle body, and between described middle body and described Outboard Sections.

4. belt according to claim 3, wherein said coating have a plurality of grooves in one of described at least two Outboard Sections.

5. belt according to claim 3, wherein said coating have a plurality of grooves in one of described at least mid portion.

6. belt according to claim 1, wherein said coating have a plurality of grooves in described Outboard Sections.

7. belt according to claim 1, wherein said base material is selected from the group that following material is formed: the extrudate piece of woven fabric, bondedfibre fabric, knitted fabric, braided fabric, polymeric material, nonwoven mesh material fabric and spiral connecting band.

8. belt according to claim 1, wherein said base material is for being wound in the material bands of a plurality of sth. made by twisting circles in a spiral manner, by continuous seam, each is twisted with the fingers circle be engaged to its adjacent turns circle, described stripping is selected from the group that following material is formed: the extrudate piece of woven fabric, bondedfibre fabric, knitted fabric, braided fabric, polymeric material, nonwoven mesh material fabric and spiral connecting band.

9. belt according to claim 1, wherein said coating are polymer resin, rubber or class rubber compound.

10. belt according to claim 2, wherein said groove has the darkest degree of depth at described middle body.

11. belt according to claim 3 wherein passes described mid portion to described Outboard Sections from described middle body, the degree of depth of described groove is successively decreased with the staged function.

12. belt according to claim 11, wherein said mid portion comprises the groove with two or more degree of depth.

13. belt according to claim 1, wherein said desired pattern comprise one or more parts that do not have groove.

14. belt according to claim 1, wherein said channel shaped becomes the repeat patterns with different in width and degree of depth.

15. belt according to claim 2 wherein, is compared with the groove that is formed at described Outboard Sections, the groove that is formed at described middle body has bigger width.

16. a method of adjusting the profile moisture of shoe-press belt comprises the following steps:

Base material is provided, and described base material has coating on its at least one surface; In comprising the described layer of groove, form desired pattern; And

Produce described desired pattern, thereby on the width of nip load zone, described nip load zone has such voidage, described voidage is resultant by the groove with different in width, transverse shape, spacing or the combination of one or more this kind features, or be combined with the different degree of depth, so that change described voidage in the expectation mode.

17. method according to claim 16, wherein the middle body in described nip load zone forms groove, and its degree of depth is greater than the groove on the Outboard Sections that is formed on described nip load zone.

18. method according to claim 16, wherein said base material is selected from the group that following material is formed: the extrudate piece of woven fabric, bondedfibre fabric, knitted fabric, braided fabric, polymeric material and nonwoven mesh material fabric and spiral connecting band.

19. method according to claim 16, wherein said base material is for being wound in the material bands of a plurality of sth. made by twisting circles in a spiral manner, by continuous seam, each is twisted with the fingers circle be engaged to its adjacent turns circle, described stripping is selected from the group that following material is formed: the extrudate piece of woven fabric, bondedfibre fabric, knitted fabric, braided fabric, polymeric material, nonwoven mesh material fabric and spiral connecting band.

20. method according to claim 16, wherein said coating are polymer resin, rubber or class rubber compound.

21. method according to claim 16, at least a portion of wherein said desired pattern does not have groove.

22. endless belt that is used for the shoe-press machine, described squeezer has cylindrical roller and arcuate pressure shoe, both form nip jointly betwixt, described belt comprises nip load zone, this zone has a width on cross-machine-direction, operate described belt, so that in operation, the described belt that has described nip load zone passes described nip, and described belt comprises:

Base material;

At least one coating at least one side of described base material;

The desired pattern of being located in the described layer comprises groove; And

Described desired pattern is made for, on the width of described nip load zone, described nip load zone has such voidage, described voidage is resultant by the groove with different in width, transverse shape, spacing or one or more above-mentioned feature combinations, or be combined with different depth, so that change described voidage, so that the voidage in the described nip load zone middle body is greater than the voidage in the described nip load zone Outboard Sections.